1. Field of the Invention
This invention relates to a color image reading apparatus, and more particularly to a color image reading apparatus having color correction coefficients.
2. Description of the Related Art
Color image reading apparatuses are now available in the line sequential reading type and the plane sequential reading type.
In the line sequential reading type, each read-in pixel offers data on R (red), G (green), and B (blue), which undergo color correction by software in the color image reading apparatus and are transmitted to the host computer.
In the plane sequential reading type, an image is read in order of R, G, and B on a page basis, and then the read-in data is sequentially transmitted to the host computer. Then, the data on R, G, and B undergoes color correction by software in the host computer, not in the reading apparatus.
Conventionally, in both the line and the plane sequential reading types, fixed color correction coefficients are set for the color correcting software.
In using of fixed color correction coefficients, if a different color image reading apparatus is connected, properly color correcting could not be carried out in the host computer. This is because each color image reading apparatus has its own color correction coefficients, which is caused by the characteristics of its optical components.